Progressive transformation of germinal centers: comparison of 23 pediatric patients to the adult population.

Approximately 10% of enlarged lymph nodes showing reactive follicular hyperplasia (RFH) will contain one or more progressively transformed germinal centers (PTGC). Comparison of 23 patients 16 yr old and younger (the pediatric group) of age to the adult population (greater than 16 yr old) indicates that most of the patients in each category present with a solitary asymptomatic enlarged lymph node (63% each group), usually cervical, and, while there may be recurrent lymphadenopathy showing RFH with PTGC (RFH/PTGC), evolution to Hodgkin's disease (HD) or other lymphomas is rare. Cases of PTGC unassociated with HD comprise the largest group: 70% (16/23 patients) of pediatric group; 60% (52/87 patients) of adult group. Five pediatric patients (22%) had antecedent HD (four males with lymphocytic predominance-nodular, NL&H HD; one female with nodular sclerosis, NSHD); this group is too small for comparison with adults. One patient (4%) subsequently developed NL&H HD; one patient had concurrent PTGC in the lymphoid rim surrounding NL&H HD. The 23 pediatric patients ranged from 4 to 16 yr (median 11, mean 11.3) with a male predominance (18 M, 5 F) similar to the adult population. Three differences occur comparing PTGC patients without associated HD from the two age groups. The less than or equal to 16 age group has a higher recurrence rate of PTGC (50 versus 23%); two or more biopsies showing PTGC after the initial biopsy was common, 19 versus 0%; and, morphologically, the pediatric cases unassociated with HD more often contain epithelioid histiocytic clusters (44 versus 0%), which may rim the PTGC.(ABSTRACT TRUNCATED AT 250 WORDS)